Eduard luhmann



(No Model.) y i E. LUHMANN.

PRGESS 0F MAKING CARBON DIOXIDE.

No. 507,741. Pafented'ot. 31., 189s.-

STATES PATENT OFFICE.

EDUARD': LUHMANN, OF ANDERNACH, GERMANY.

Pizoclass'oF MAKING CARBON DloxlDE.

SPECIFICATION forming part of Letters `Patent No. 507,741, dated October 31, 1893.

l Application filed July 11, 1891. Serial No. 399,250. (No specimens.)

To aZZ whom t'may concern:

Be it known that L EDUARD LUHMANN, a subject of the King of Prussia, German Emperor, and a residentof Andernach, in the Province of the Rhine, Kingdom of Prussia, Empire of Germany, have invented certain new and useful Improvements in Processes of Extraction of Gases from Fluids, of which the following-is a full, clear, and exact specitlcation, reference being had to the accompanying drawing, which forms a part of this specification. v

My invention relates to a method of extracting gases'from iiuids in a continuous way by decomposing and regenerating the latter, and consists ineffecting the decomposition in two stages, extracting the main portion ofthe I nace of any suitable construction.

gases at a pressure but very little exceeding the atmosphericpressure, and the remaining portion at a pressure of from one and a half to two atmospheres. l

Inorder to perform my process I employ an apparatus of the kind illustrated by the accompanying drawing, which is-a longitudinal sectional elevation of the said appartus. The closed boiler o, is placed within a fur- In the upper part of the boiler shell the pipe Z is passed through a suitable hole in the same, and reaches down nearly to the bottom of the said boiler. The pipe Z leads into a cooling tank Z', in which it forms a coil, and leaves the same by means of the pipe Z2, which is connected with the absorption tower h, and provided at its extremity, in the upper part of the said tower b, with a rose of any appropriate construction. This absorption tower b Vis filled in its greater part with fragments of coal or of any other material presenting a large surface, said material resting on a perforated plate provided a short distance above the bottom of the absorption tower b. A pipe 'n' leads from the bottom of the latter to the collecting vessel or tank n. Immediately below the above mentioned perforated plate on which the fragments of coal rest, I provide another pipe h which communicates with the top of the washing cylinder c, which is constructed similar to the absorption tower b. This cylinder is filled with fragments of marble resting on a perforated plate, below which there is provided a pipe c. Above the Washyinto the collecting vessels.

the absorption tower b and washing cylinder c are hermetically closed. Above the collecting tank n there is provided a forcing pump 10,. from which a pipe descends into said tank n, While another pipe n2 leads from the pump p into the upper part of a boiling vat la. In the lower part of the latter I arrange several perforated tubes, which are all in communication with the pipe fr coming from the dome at the top of boiler a. At the top of the boiling vat lc I provide a pipe lo communicating with a cooler .102, which is supplied with water from a reservoir w by means of a pipe wz. The pipe on the right at the bottom of cooler k2 is for draining off the water by opening a suitable cock (not shown on the drawing), and the pipe leaving said cooler at the bottom on the left leads From the top of the latter a pipe s2 leads to the gasometer, not shown on the drawing, while the pipe at the bottom of said collecting vessel leads into the tank t. Into the latter are also led the pipes m and c, the former from the lower part of boiling vat k, and the latter communicating with a forcing pump p2, from which a pipe e leads into the boiler o. v

I will now describe my improved process as applied tothe production of carbonio acid from bicarbonate of soda.

The boiling vat lc is filled with a bicarbonate of soda solution of 10" Baume, the reservoirs w and w and coolers k2 and Z being filled with water. Boiler a is likewise partly Iilled with water or with a Weak lye of carbonate of soda. This solution is heated till it boils thoroughly and the steam evolved escapes through the pipe r into the boiling vat lo. The liquid itselfI will assume that a weak lye is employed-rises in pipe Z and iiows through the serpentine coil placed in the cooler Z', where it is brought to the temperature which will enable it to absorb the maximum amount of carbonio acid. Hereafter the lye proceeds through the connecting pipe Z2 to the absorption tower b and issues in the top of the same through the rose provided at the end of the pipe. At the same time carbonio acid produced in any usual IOG ters the absorption tower b at the bottom zby 1 the pipe b and moves in this towerin the opposite direction to the lye, which travels downward. In consequence thereof, the lye ,l

may absorb a great quantity of carbonic acid and is thus converted into a solution of biable for practical reasons that the boiling carbonate or at least sesquicarbonate of soda. This liquid leaves the absorption tower by the pipe ot" and flows into the collecting vessels or l tank fn, whence it is conveyed into the boiling vat 7c bymeans ofthe pum-p p and through the pipen. The boiling vat kisheatediby means of the `steam emanating `from `the boiler -ct and entering the same through the perfo` rated :pi pes located at thelbottom. The steam then heats and decomposes thelye to such an extent that it gives .olf `most of thecarbonic acid which it contains which becomes mixed with vthat carried -away with the steam from boiler ct. The `carbonio rac'id which is thus freed passes through pipe lo into the cooler 7a2 supplied with Water from reservoir tu', and thence into the collecting `vessel s, where'the condensed water is collected, while the carbonio acid is conducted by means of pipe s2 tothe gasometer. The water proceedingfrom condensation in vessel s is allowed to run into tank t so as to maintain a uniform -concentration of the lye. This is absolutely necessary, as otherwise the lye would become-so dense, .as to be unable to retain the salt 'in solution, but would throw itlof and clog the pipes. The hot lye coming from the boiling Vat 7c which runs out of same into the vessel t through the pipe m is not yet freed of all the bicarbonate or sesquicarbonate of soda which it holds in solution. It is stillto The .carbonio acid rising in the washing a certain extent undecomposed and would not only, if used again in `that state, hamper the production of carbonic gas to a great extent, but it would be very difficult to regenerate this impure residue lye into bicarbonateor sesquicarbonate of soda, that is to say, that the small absorbent power of this in1- pure lye would greatly impede the further processes. To avoid this the impure lye is taken up by the pump p2 by means of pipes e e and pumped into boiler a.

It will be understood that the process is a continuous one, and therefore may be kept up for any length of time, but it is prefershould be continued `for one hour at least. The chief advantage of the described process is that :it permitsof la complete and thorough utilization of the heat generated, while facilitating the processes throughout.

'The same process may 'be employed lfor producing carbonio acid from bicarbonate of potash, and the most advantageousstrength of the solution will be l`7 Baume.

Having thus fully described the `nature of this invention, what I desire Vto secure by Letters Patent of the United States is- The `method o'f producing carbonio :acid from liquors containing `sesqui or bicarbonate,said method consisting in first heating the "liquor in a boiling vat at low pressure, thereby expelling the main part of `the carbonic acid, then vboiling the liquor or lye under `high pressure in a closed boiler and thereby simultaneously concentrating the lye; the steam and the carbonicacidevolved being used for heating the lye in the boiling vat, substantially as described.

In testimony whereof I have signed this specification in the presenceof two subscribing witnesses.

EDUARD LUHMANN. lVitnesses:

OTTO BRAEGER, WILLIAM OELRIGHS. 

